The present invention relates to disc brakes in general, and more particularly to a floating-caliper spot-type disc brake.
Conventional brakes of this type usually include a brake carrier member which is preferably located at the inner side of the wheel. Two brake-shoe carrying and guiding webs extend substantially radially from the carrier member in a circumferentially spaced relationship. These webs axially straddle the brake disc and directly support the brake shoes. A floating caliper member is interposed between the brake-shoe carrying and guiding webs and carries a hydraulic piston-and-cylinder arrangement on the inner side of the wheel. The caliper member transmits the clamping or braking force to the outward brake shoe which is situated across the brake disc from the piston-and-cylinder arrangement. The floating caliper member is axially guided by at least one axial bolt supported at the brake support member. The floating caliper member has on one circumferential side in the area of the outward brake shoe a tooth-shaped extension engaging from radially inwardly a stop of the brake-shoe carrying and guiding webs. Both circumferential sides of the floating caliper member are guided in a circumferential direction between the brake-shoe carrying and guiding webs.
There are also already known floating-caliper spot-type disc brakes of different designs, among them such wherein the floating caliper member is arranged in a fist-type manner between brake-shoe carrying and guiding webs of the brake carrier member and is guided by axial guiding pins provided at the brake carrier member. It is also possible to have the guiding pin formed at the floating caliper member and guided in a bushing of the brake carrier member, as disclosed in German published patent application No. 25 38 565.
To hold the floating or fist-type caliper member securely in position in a floating-caliper spot-type disc brake of this type not only in the circumferential direction but also in the radial direction, the floating caliper member has on its one side an extension or tooth by means of which it is hooked underneath a stop at the brake-shoe carrying and guiding web. It is a disadvantage of this arrangement that, during replacement of the brake shoes, the floating caliper member has to be urged against a brake shoe holding spring to enable mounting of the axial guiding pins. An accurate guiding of the caliper member is possible in this known arrangement only by using two axial guiding pins which are suitably disposed on both sides of the cylinder housing of the piston-and-cylinder unit. This, of course, limits the design choices and renders the disc brake unnecessarily expensive.